The purpose of this project is to develop improved membrane lungs and membrane lung systems for prolonged pulmonary and cardiopulmonary support. Major activities center around 1. improved blood compatible membranes suitable for use in membrane lungs and blood conduits, 2. develop a carbon dioxide membrane lung for efficient blood carbon dioxide removal, 3. investigate methods to optimally apply the carbon dioxide membrane lung for the control of breathing in health and disease, and 4. investigating the nature of pulmonary capillary blood flow under normal conditions, and under conditions of increased airway pressure.